JPH0531400A - Dehydration device - Google Patents

Abstract

(57) [Summary] [Purpose] To make it possible to keep the water content of a gypsum cake stable at around 5 to 15% without manpower. [Structure] Slurry 4 fed from slurry supply pipe 3
In the dehydrator 2 for centrifugally separating the water 12 and the cake 10 by utilizing the rotation and the speed difference between the inner case 5 and the screw 14, the flowmeter 24 and the densitometer 2 are provided in the middle of the slurry supply pipe 3.
5 is provided, and based on the flow rate detection signal 27 from the flow meter 24 and the concentration detection signal 28 from the densitometer 25, the drive device 9 for rotating the inner barrel 5 and the drive device 2 for rotating the screw 14 are provided.
An arithmetic and control unit 26 is provided which calculates the rotational speed of No. 3 and outputs control signals 29 and 30 to the drive units 9 and 23 based on the rotational speed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dehydrator.

[0002]

2. Description of the Related Art In a desulfurization facility utilizing the lime-gypsum method, a gypsum slurry discharged from a desulfurization device is centrifugally separated into water and a gypsum cake by a dehydrator in a subsequent process.

Here, it is necessary to set the water content of the centrifugally separated gypsum cake to about 5 to 15% from the viewpoint of economical efficiency of operation of the dehydrator and handling of the gypsum cake.
The water content of the gypsum cake, that is, the dehydration amount of the gypsum slurry in the dewatering device is adjusted by the rotation speed of the inner cylinder and the differential speed between the inner cylinder and the screw. In order to keep it at about 15%, conventionally, an operator manually adjusts the rotation speed of the inner case and the differential speed between the inner case and the screw.

[0004]

However, when an operator manually adjusts the rotation speed of the inner case and the differential speed between the inner case and the screw, a skilled worker is required. Another problem is that it is difficult to always keep the water content of the gypsum cake stable at about 5 to 15%.

In view of the above situation, it is an object of the present invention to provide a dewatering device which can always keep the water content of a gypsum cake stably at about 5 to 15% without manpower. Is to

[0006]

DISCLOSURE OF THE INVENTION The present invention relates to a dewatering device for centrifuging slurry fed from a slurry feed pipe into water and a cake by utilizing the rotation and the differential speed between an inner barrel and a screw. A flowmeter and a densitometer are installed in the middle of the supply pipe, and the rotation speed of the drive unit for rotating the inner barrel and the drive unit for rotating the screw is determined based on the flow rate detection signal from the flowmeter and the concentration detection signal from the densitometer. And a calculation control device that outputs a control signal to each drive device based on the rotation speed.

[0007]

According to the present invention, based on the flow rate detection signal and the concentration detection signal from the flowmeter and the densitometer provided in the middle of the slurry supply pipe, the arithmetic and control unit is provided with a drive unit for rotating the inner barrel and a screw for rotating the screw. Calculate the rotation speed of the drive of
Based on the rotation speed, the arithmetic and control unit outputs a control signal to each drive unit to change the rotation speed and the differential speed between the inner case and the screw.

As a result, the water content of the cake obtained by centrifuging the slurry is stably maintained at a constant value.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention.

In the figure, 1 is a desulfurization device using the limestone gypsum method,
Reference numeral 2 is a dehydrator, and 3 is a slurry supply pipe for feeding a slurry 4 such as gypsum slurry discharged from the desulfurizer 1 to the dehydrator 2.

Denoted at 5 is a hollow inner case forming the dehydrating device 2, both ends of which are rotatably supported by bearings 6, and
The outer periphery of one end is connected to a driving device 9 such as a motor (hereinafter, simply referred to as a motor 9) via a belt 7 and a pulley 8, and a slurry supply pipe 3 is inserted from one end to the inside.

The inner body 5 of the dewatering device 2 has a discharge port 11 for a cake 10 such as a gypsum cake that has been centrifugally separated on one end side, and a drain port 13 for water 12 on the other end side. , And has a shape in which the diameter is reduced from the central portion toward the discharge port 11 side of the cake 10.

Reference numeral 14 denotes a hollow screw rotatably supported inside the inner case 5 via a bearing 15. The slurry supply pipe 3 is inserted into the interior from one end side and the open end 16 of the slurry supply pipe 3 is inserted. Slurry 4 in the vicinity of the inner body 5
The rotary shaft 18, which has a plurality of discharge ports 17 for discharging to the side, and which penetrates the inner case 5 at the other end side, the speed reducer 19, and the pulley 2.
It is connected to a driving device 23 such as a motor (hereinafter, simply referred to as a motor 23) via 0, a belt 21, and a pulley 22.

Reference numeral 24 is a flowmeter for the slurry 4 provided in the middle of the slurry supply pipe 3, and 25 is a concentration meter for the slurry 4 provided in the middle of the slurry supply pipe 3.

26 is a flow rate detection signal 27 from the flow meter 24.
And a density detection signal 28 from the densitometer 25 to calculate the rotational speeds of the motor 9 for rotating the inner cylinder 5 and the motor 23 for rotating the screw 14 and output control signals 29 and 30. is there.

Next, the operation will be described.

A slurry 4 such as a gypsum slurry discharged from a desulfurization apparatus 1 utilizing the lime-gypsum method is fed to a dehydrator 2 via a slurry supply pipe 3.

At this time, in the dehydrator 2, the motor 9 for rotating the inner case 5 is driven to drive the inner case 5 through the pulley 8 and the belt 7.
Motor 23 for rotating the screw 14 while rotating
To rotate the screw 14 via the pulley 22, the belt 21, the pulley 20, the speed reducer 19 and the rotary shaft 18, and to make the inner case 5 and the screw 14 have a differential speed as described later. To do.

Then, the slurry 4 supplied from the opening end 16 of the slurry supply pipe 3 into the screw 14 is discharged from the discharge port 17 formed in the screw 14 into the space between the inner case 5 and the screw 14, In the space, the cake 10 and the water 12 are separated by the centrifugal force due to the rotation of the inner case 5 and the screw 14 and the differential speed between the inner case 5 and the screw 14. 12 is moved to the other end side of the inner case 5, and is discharged from the discharge port 11 and the drain port 13, respectively.

Here, the water content of the cake 10 is 5 to 15%.
The flow rate detection signal 27 is detected by the flow meter 24 provided in the middle of the slurry supply pipe 3 in the present invention, though it is necessary to set the degree to the economical efficiency in the operation of the dehydrator and the handling of the gypsum cake. At the same time, the concentration detection signal 28 is detected by the concentration meter 25, and the flow rate detection signal 27 from the flowmeter 24 is detected.
And a concentration detection signal 28 from the densitometer 25 are input to the arithmetic and control unit 26, and the arithmetic and control unit 26 uses the flow rate detection signal 27 and the concentration detection signal 28 to rotate the motor 9 for the inner cylinder 5 rotations and the screw 14 rotations. The rotation speeds of the motors 23 are calculated, and the control signals 29 and 30 are output to the motor 9 for rotating the inner cylinder 5 and the motor 23 for rotating the screw 14 to control the rotation speeds of the motors 9 and 23.

That is, in general, when the dewatering capacity of the dewatering device 2 is constant, the load acting on the dewatering device 2 increases as the inflow amount of the slurry 4 increases or the concentration of the slurry 4 increases. The water content of the cake 10 increases, and conversely, as the inflow amount of the slurry 4 decreases or the concentration of the slurry 4 decreases, the load acting on the dehydrator 2 decreases and the water content of the cake 10 decreases. Therefore, if the flow rate detection signal 27 detected by the flow meter 24 becomes large or the value of the concentration detection signal 28 detected by the densitometer 25 becomes large, the rotation speeds of the motors 9 and 23 are controlled to control the inner body 5 The rotation speed of the inner cylinder 5 and the screw 14
The water content of the cake 10 is lowered by increasing the speed difference with the water to enhance the dehydration ability, that is, the centrifugal separation effect, and the flow rate detection signal 27 detected by the flow meter 24 is reduced or detected by the densitometer 25. When the value of the density detection signal 28 becomes small, the rotation speeds of the motors 9 and 23 are controlled to slow down the rotation speed of the inner case 5, and the differential speed between the inner case 5 and the screw 14 is made small. By lowering the centrifugal separation effect, the moisture content of the cake 10 is increased.

As a result, the water content of the cake 10 can be automatically maintained within the range of 5 to 15%, preferably 7 to 12%.

The present invention is not limited to the above-mentioned embodiments, and it goes without saying that various changes can be made without departing from the scope of the present invention.

[0025]

As described above, according to the dehydrator of the present invention, the water content of the gypsum cake is always stable at about 5 to 15%, preferably 7 to 12%, without requiring human labor. It has an excellent effect that it can be kept inside.

[Brief description of drawings]

FIG. 1 is an overall view of an embodiment of the present invention.

[Explanation of symbols]

 2 Dewatering device 3 Slurry supply pipe 4 Slurry 5 Inner body 9,23 Drive device 10 Cake 12 Water 14 Screw 24 Flow meter 25 Concentration meter 26 Arithmetic control device 27 Flow rate detection signal 28 Concentration detection signal 29, 30 Control signal

Claims (1)

Claim: What is claimed is: 1. A slurry supply pipe in a dewatering device for centrifuging slurry fed from a slurry supply pipe into water and a cake by utilizing rotation and a differential speed between an inner barrel and a screw. A flow meter and a densitometer are installed in the middle of the process, and the rotational speeds of the drive unit for rotating the inner cylinder and the drive unit for rotating the screw are calculated based on the flow rate detection signal from the flow meter and the concentration detection signal from the densitometer. Then, the dehydration apparatus is provided with an arithmetic and control unit that outputs a control signal to each drive unit based on the rotation speed.